Attorneys for the defendant, Aaron Ybarra, 26, have said their client suffers from "significant and long-standing mental health issues" that were a factor in the shooting this month at Seattle Pacific University.

. . .

In court documents, prosecutors say Ybarra confessed to police detectives that he had been planning a mass shooting in which he wanted to kill as many people as possible before committing suicide.

They said entries in a journal he kept expressed admiration for the massacres committed at Columbine High School in Colorado in 1999 and Virginia Tech in 2007.